L. Backstrom, and J. Leskovec. Proceedings of the fourth ACM international conference on Web search and data mining, page 635--644. New York, NY, USA, ACM, (2011)
A. Java, X. Song, T. Finin, and B. Tseng. Proceedings of the 9th WebKDD and 1st SNA-KDD 2007 workshop on Web mining and social network analysis, page 56--65. ACM, (2007)